Focus coil support and control



P 1951 J. HOELLERICH 2,568,531

FOCUS COIL SUPPORT AND CONTROL Filed Jan. 27, 1950 INVENTOR. CI'ZAILEZY:15 0671422101 39 1 a 16 v 17 J6 g g patented Sept. 18, 1951 John L.Hoellerich, Wilmette, Ill., assignor to Admiral Corporation, Chicago,111., a corporation of Delaware Application J anuary 27, 1950, SerialNo. 140,870 12 Claims. (01. 313-84) This invention relates to mechanismsfor support of the coils commonly associated with the electron gun of acathode ray tube, and means by which the coils are adapted to bepositioned when moved for best operation of the cathode ray tube.

The invention comprehends, in addition, to means by which the deflectioncoils are adapted to be positioned for best cooperation with a cathoderay tube, means by which the position of the focus coil is adapted to bepositioned; independently of the deflection coils, from a pointexteriorly of the wall of a cabinet in which the cathode ray tube andcoils are disposed, without danger of shock to a person by whom such anadjustment is made or danger to the person from fragments of glass incase of fracture of the tube.

In earlier mountings for the focus coils of cathode ray tubes, it wascustomary to support said tubes by means which included screwadjustments and springs for applying forces in opposite directions tocasings in which the focus coils were mounted for regulating thepositions thereof. This enabled the position of the raster on the screento be adjusted. The main disadvantage of this manner of adjustmentresided in the fact that a screw driver orwrench had to be used, whichwas not only slow but either required the use of a mirror, so that theperson standing at the rear and making the adjustment could see whichway the raster was being moved, or the services of a second person toinform the, person adjusting the focus coil of the results. Furthermore,this type of adjustment was exceedingly slow. Then very frequently, evenafter adjusting, the adjustment changed in time due to slippage f thesprings. Too often, due to the use of the screws, the tube was brokenoff at the neck due to the pressure of the focus coil on the neck, whichpressure could not be readily be determined d ue to the fact that it wasbeing applied with screws.

Furthermore, it was possible to make these adjustments only after a rearcover of the cabinet, in which the cathode ray tube was mounted, wasremoved. And this could be responsible for se- Vere electrical shockto aperson attempting such an adjustment, or from flying glass should thewall structure of the cathode ray tube become fractured.

In the present invention means is provided by which the focus coil isadapted to be effectively moved from the exterior of the cabinet withoutthe necessity of gaining access to the interior thereof for e'if ectingthis adjustment. Consequently, the hazardous risk of contact viii'tl'rhigh tension conductors and/0r highly" charged sin"- faces is avoided,and in addition, glass fragments, occasioned by possible breakage of thecathode ray tube, are confined within the cabinet.

Briefly, the invention contemplates us of extendable mechanism passingthrough an aperture in one of the walls, usually the rear wall, of acabinet from the exterior of which manual forces are adapted to becommunicated to the focus coil to adjust the same independently of thedeflection coils, and means by which the deflection coils and focuscoils are adapted to be collectively stationed with respect to theelectron gun portion of a cathode ray tube, especially if said electrongun portion is out of alignment with the larger diametral portion of thetube. Furthermore, barrier means coupled to the extendable mechanism, isprovided to exclude the hands of an attendant from entrance to theinterior of the cabinet through an aperture through which the extendablemechanism is adapted to pass, and/or an electrically conductiveinstrument extended through said aperture regardless of theposition inwhich the extendable mechanism is stationed. 7 Other advantages of theinvention will be set forth in part hereinafter and in part will beobvious herefrom, or may be learned by practice with the invention, thesame being realized and attained by means of the instrumentalities andcombinations pointed out in the appended. claims.

In the drawings: s Fig. 1 is a side elevational view of the invention;

Fig. 2 is a fragmentary transverse section taken on line 2-2 of Fig. l,a portion of the mechanism being broken away to reveal the structure ofunderlying parts; and Fig. 3 is a vertical section taken on line 3-3 ofFig. 1.

Throughout the drawings, wherein fort-he purpose of illustration, isshown one embodiment of the invention, the reference character l is usedtodenote a fragment of the top of a chassis for a kinetescope or acathode ray tube installation such as as employed in a televisionreceiving set. Chassis I is adapted to be mounted in a cabinet of whichonly a fragmentary portion of the rear wall 2 is shown. Although acathode ray tube 3 having an elongated portion or neck 4, of uniformdiameter, is indicated in association with other apparatus, later to bedescribed, .it derives its support in a manner not shown. Theneck 4embraces means by which a beam of electrons is projected from: right toleft Fig. 1) and which is adapted to bereflected during it passagethrough the tube by deflection coils 5 supported 3 from a centralportion or arch 1 of a yoke 8 for adjustment of the coils angularly andlongitudinally of the neck 4 by means including a bolt 9. Provision forthis adjustment further includes a slot II, in the arch 1, through whichbolt 9 passes. The yoke 8 is supported by a bearing frame I2 comprisinga pair of vertical standards I3 which are bolted to the chassis I.Upwardly thereof, the frame I2 is embraced by arms I4 and I6 whichextend downward from the ends of the arch 1 and are releasably clampedto the upper ends of standards I3 by screws I1, threaded in saidstandards and in coaxial relationship to each other. Also, the screws I1may have suitable washers 26 under their heads, if desired. At the leftthereof, arms I4 and I6 are embraced by a pair of flanges I8 bentbackward from an apertured grommet support I9 for support of a rubbergrommet 2|, which bridges the ends of arms I4 and I6 to which flanges I8may be rigidly secured in any convenient manner.

Means is provided to adjust the yoke 8 with respect to the standards I3.This is advisable since, owing to imperfections in manufacture ofcathode ray tubes, the axis of the neck 4 may be inclined slightly fromthe axis of the larger portion thereof including the screen.Accordingly, the screws I1 provide a substantially horizontal axis aboutwhich yok 8 and the arms I4 and I6 are adapted to be swung until theaxes of the coils substantially coincide with the axis of the neck. Oncethe arms I4 and I6 have been thus swung tocompensate for misalignment ofneck 4 with the rest of tube 3, the yoke 8 is locked to the frame I2.This is affected by tightening a clamp screw 22 which is threaded in oneof the standards I3 and passes through a slot 23, arcuate of the axes ofscrews I1.

The focus of the cathode ray tube 3 is adapted to be regulated by afocus coil 24. It is enclosed preferably by a metal casing 26 andpivotally coupled to the arms I4, and I6 of the yoke 8 by meansincluding a gimbal ring 21. Ring 21 comprises a U-shaped member 28 and astrap member 29 bolted to the two ends of the U-shaped member. Centrallyof both the top and bottom of casing 26, threaded studs 3i, in coaxialrelationship with each other, are in vertical extension through thestrap 29 and a central section 32, parallel to the strap, of theU-shaped member 28. The studs 3| bear nuts 33 adapted to clamp casing 26to itssupports which operation may be improved by use of washers 34 andspring washers 36 under the nuts.

Since it is essential that the focus coil be orientable about the axisprovided by the studs 3|, suflicient friction is afforded by the springwashers 36 to retain the focus coil in whatever position it is moved towithout unduly resisting manual effort when altering the position of thefocus coil. It is also essential that the focus coil be swingable abouta horizontal axis which is provided by a pair of bushings 31 passingthrough continuations of the arms I4 and I6 and into abutment withparallel, vertical sections 38 and 39 of the U-shaped member 28. Thestate of abutment of the bushings 31 with sections 38 and 39 is providedby the clamping action of screws 4| passing freely through the bushings31, and threaded in said sections 38 and 39 assisted by lock washers 42.Additionally, resistance to motion of the focus coil 24 about itshorizontal axis is also provided so that said coil will remain inwhatever position it is stationed. To this end, the bushings 31 areprovided with flanges 43 at their outer 4 ends which are spaced from thearms I4 and I5 but only slightly more than the thickness of springwashers 44 so that the washers 44 are maintained under deflectionbetween flanges 43 and the arms I4 and IS.

The focus coil 24 is adapted to be rocked about its axes from a pointexteriorly of the wall 2. In order that this may be carried out, abracket 'member 46 is employed. It includes a lateral foot portion 41which is rigidly secured in any convenient manner, to the casing 26while in offset relationship to foot 41 is a cantilevered portion 48 inwhich a thumb screw 49 is threaded. The screw 49 is adapted to extendthrough any one of a series of slots 5I in a beam 52 so that theposition of said beam is adapted to be altered, longitudinally thereof,with respect to the bracket 46. This is in order that one size of beam52 may 'be used for several cabinets varying in size. Beam '52 isthereby adapted to extend far enough through an aperture 53, in the wall2, to provide a handle portion 54 outside of the cabinet. As aprecaution against rotation of the beam about screw 49, opposite edgesof said beam are flanged as at 56 so as to embrace the opposed edges ofthe bracket at portion 48 thereof. The flanges 56 extend from the leftextremity of the beam to the handle 54 which is of decreased width to apoint well within the wall 2 whereat a pair of shoulders 51 are providedat the right hand end of flanges 56.

Particularly in cabinets for domestic television receiving sets, thebacks thereof are closed by a removable wall such as the wall 2, usuallyof foraminous construction, to exclude the hands of persons liable toreceive an electric shock from apparatus within the cabinet: Therefore,it is advisable or essential that the aperture 53 be closed without inany way hampering, the capacity of the handle 54 to be moved laterallyfor adjustment of the focus of the television receiver. Accordingly, thebeam 52 extends through a barrier, shield or flat plate 58 of area andproportions of such a nature that, regardless of the position of thathandle 54 is stationed in with respect to the edge of aperture 53, thebarrier 58 will cover said aperture. The operation of maintaining theaperture 53 closed regardless of the position of beam 52 is furtheraugmented'by a spring 59 in compression on the handle portion 54 betweenshoulders 51 and the shield 58. Due

to this construction, it would :be difiicult to even shock to a person.

If desired, a cotter Or pin 5| may be carried by the handle portion.54to resist too ready removal of the plate 58 if and when the rear cover 2is removed for servicing of the chassis. In operation, the handle 54 maybe moved within the limits of the aperture 53, which movement is ampleto allow the proper positioning of the raster on the screen. Since thelimits of the aperture 53 restrict the movement of the control handle,and hence the angular movement of thefocus coil, there is substantiallyno chance of the neck of the tube being broken. Furthermora'because itis simple and quick to effect the adjustment,

it is even within the province of the unskilled to make the adjustmentof the raster in a simple and easy manner. 7

While I have described my invention in an embodiment thereof, I am awarethat numerous and extensive departures may be made therefrom.

without departing from the spirit or scope invention.

I claim:

1. The combination with a focus coil supported by a gimbal ring foroperative association with a cathode ray tube within a cabinet having anaperture in one of the walls thereof, of an extension mechanism coupledto the focus coil by which said focus coil is adapted to be moved aboutits axes, adjustment means in connection with the extension mechanism toprovide forpextension of said mechanism an operative distance throughsaid aperture, and means in connection with said extension mechanism bywhich said aperture is adapted to be closed regardless of the extent towhich said extension mechanism is moved about its axes.

2. The combination with a focus coil in operative association with acathode ray tube within a cabinet having an aperture in one of the wallsthereof, of a gimbal ring comprising a yoke and a strap to support thefocus coil, separate means in connection with the yoke to provide one ofthe axesfor the ring, means engaged between said yoke and said strap toprovide another of the axes for said ring, an extension mechanism cou--pled to the focus coil by which said focus coil is adapted to be movedabout its axes, adjustment means in connection with the extension mech--anism to provide for extension of said mechanism an operative distancethrough said aperture and thereby provide for movement of the coil fromthe exterior of the cabinet and barrier means in connection with saidextension mechanism by which said aperture is adapted to be closedregardless of the extent to which said extension mechanism is moved.

3. In a cabinet having a rear wall in which an aperture is disposed andwithin the cabinet is housed a television receiving set which includes acathode ray tube with which is operatively associated a focus coilsupported by a gimbal ring, the combination of, means including abracket element coupled to the focus coil by means of which said coil isadapted to be swung about its axes from a point exteriorly of thecabinet, a beam element, one of said elements having at least one slottherein, a threaded member in extension from the other element throughsaid slot to adjustably clamp said elements together thereby providingfor operative extension of said beam element through the aperture, aplanar member carried by said beam element, said planar memher being ofarea greater than the area of said aperture, a spring to urge saidplanar member against the cabinet wall at said aperture to close saidaperture, said planar member being coupled to said beam element toprovide for continued closing of said aperture regardless of theposition to which said beam element is moved.

4. A mounting for a set of coils including a focusing coil and a pair ofdeflection coils adapted to operate a cathode ray tube having a neckwith which the coils are in association comprising a stationary member,an annular mechanism providing support for said focusing coil, saidannular mechanism also providing an axis about which said focusing coilis adapted to be rocked, a yoke member, said deflection coils beingsupported by said yoke member, first pivotal means to pivotallyassociate said yoke member with said stationary member, second pivotalmeans to pivotally associate said annular mechanism with said yokemember thereby providing a second axis in angularly spaced relationshipto said first mentioned of my stages:

6 axis for the focusing coil, all the coils being adapted to be swungabout said first pivotal means to be operatively positioned with respectto the neck of the cathode ray tube and locking means adjacent saidfirst pivotal means to clamp said yoke member in the position to whichit is moved.

5. A mounting fora set of coils including a focusing coil and a pair ofdeflection coils adapted to operate a cathode ray tube having a neckwith which the coils are in association within a cabinet having anopening in one of the walls thereof comprising a stationary member, anannular mechanism providing support for said focusing coil, said annularmechanism also providing an axis about which said focusing coil isadapted to be rocked, a yoke member, said deflection coils beingsupported by said yoke member, first pivotal means to pivotallyassociate said yoke member with said stationary member, second pivotalmeans to pivotally associate said annular mechanism with said yokemember thereby providing a second axis in angularly spaced relationshipto said first mentioned axis for the focusing coil, all the coils beingadapted to be swung about said first pivotal means to be operativelypositioned with respect to the neck of the cathode ray tube, lockingmeans adjacent said first pivotal means to clamp said yoke member in theposition in which it is moved to and extension mechanism coupled to saidfocusing coil and in extension through the opening, said focusing coilbeing adapted to be thereby swung about its axes from a point exteriorlyof the cabinet when said yoke member is clamped to said stationarymember.

6. A mounting for a set of coils including a focusing coil and a pair ofdeflection coils adapted to operate a cathode ray tube having a neckwith which the coils are in association within a cabinet having anopening in one of the Walls thereof comprising a stationary member, anannular mechanism providing sup-port for said focusing coil, saidannular mechanism also providing an axis about which said focusing coilis adapted to be rocked, a yoke member, said deflection coils beingsupported by said yoke member, first pivotal means to pivotallyassociate said yoke member with said stationary, member, second pivotalmeans to pivotally associate said annular mechanism with said yokemember thereby providing a second axis in angularly spaced relationshipto said first mentioned axis for the focusing coil, all the coils beingadapted to be swung about said first pivotal means to be operativelypositioned with respect to the neck of the cathode ray tube, lockingmeans adjacent said first pivotal means to clamp said yoke member in theposition in which it is moved to, extension mechanism coupled to saidfocusing coil and in extension through the opening, said focusing coilbeing adapted to be thereby swung about its axes from a point exteriorlyof the cabinet and barrier means coupled to said extension means, saidbarrier means being adapted to close said aperture in any position inwhich the extension mechanism is moved to.

'7. A mounting for a set of focus and deflection coils adapted tooperate a cathode ray tube having a neck with which the coils are inassociation within a cabinet having an opening in one of the wallsthereof comprising a stationary member, an annular mechanism providingsupport for a focus coil, said annular mechanism also providing an axisabout which said focus coil is adapted to be rocked, a yoke member, thedeflection coils being supported by said yoke member,

first pivotal means to pivotally associate said yoke member with saidstationary member, second ivotal means to pivotally associate saidannular mechanism with said yoke member thereby providing a second axisin angularly spaced relationship to said first mentioned axis for thefocus coil, all the coils being adapted to be swung about said firstpivotal means to be operatively positioned with respect to the neck ofthe cathode ray tube, locking means adjacent said first pivotal means toclamp said yoke member in the position in which it is moved to,extension mechanism including a first element coupled to said focuscoil, a second element adapted to extend through the cabinet opening, ashield member coupled to the second element, clamping means toextendably secure said second element to said first element forextension of said second element through said opening, said shieldmember then being adapted to overlie said opening and resilient meanscoupled to said second element to bias said shield member intoengagement with said cabinet wall at said opening thereby closing saidopening, said second element providing exteriorly of said wall a handleby which the focus coil is adapted to be regulated.

8. A support for a focus coil for a pictur tube in a televisionreceiver, including, a base support having portions disposed on oppositesides of the neck of the tube, a pair of arms pivotally connected tosaid support and extending alongside said neck, a gimbal ring carriedbetween said arms and a focus coil carried by the gimbal ring, meansconnected to said focus coil for moving the same on its support.

9. A support for a focus coil for a picture tube in a, televisionreceiver having a cabinet, including, a base support having portionsdisposed on opposite sides of the neck of the tube, a pair of armspivotally connected to said support and extending alongside said neck, agimbal ring carried between said arms and a focus coil carried by thegimbal ring, means connected to said focus coil extending through saidopening in the wall of said cabinet for moving said coil, a closuremember disposed on the means connected to the focus coil, and held inengagement with said cabinet wall and covering said opening at alltimes.

10. A mounting'for the deflection and focus coils of a cathode ray tubeincluding a base member, ayoke member pivotally mounted on said basemember, said deflection coils, being adjust- 8 ably mounted on said yokemember, locking means adapted to lock said yoke member in an adjustedposition on said base member, and a gimbal ring pivotally mounted onsaid yoke member laterally displaced from said-deflection coils, saidfocus coil being v ivotally mounted in said ring on a pivot axisangularly displaced from the pivot axis between said ring and said yokemember.

11. A support for the deflection and focusing coils of a cathode raytube comprising a base member, a support member adjustably mounted onsaid base member and adapted to be held in a plurality of adjustedpositions, said deflection coils being mounted on said support memberand a gimbal ring mounted on said support member adapted to hold saidfocusing coil in a universally adjustable relationship to said tube.

12. A support for the deflection and focusing coils of a cathode raytube comprising a stationary base member having a pair of vertical arms,a support member pivotally mounted on said base member at a pivotalaxis, one of said members being formed with at least one slot arcuate ofsaid axis, screw means threaded into the other of said members extendingthrough said slots to clamp said support member in an adjusted positionon said base member, said deflection coils being adjustably mounted on'said support member and a. gimbal ring mounted on said support memberadapted to hold said focusing coil in a universally adjustablerelationship to said tube.

JOHN L. HOELLERICH.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,165,779 Blain July 11, 19392,234,720 De Tar Mar. 11, 1941 2,428,928 Cain Oct. 14, 1947 2,440,403Jackson, Apr. 27, 1948 2,443,973 Asling June 22, 1948 e 2,471,154 KeimMay 24, 1949 2,479,494 Jackson Aug. 16, 1949 2,521,061 Heisig Sept. 5,1950 FOREIGN PATENTS Number Country Date 597,255 Great Britain Jan. 21,1948

